The diagnostic strategy to be used for a bone tumor depends on the
ability of the clinician to make an accurate differential diagnosis on the
basis of clinical information and plain radiographs. The clinician must be
able to classify the patient as having a non-progressive or a progressive
primary benign bone tumor, a primary malignant bone tumor, or a metastatic
bone tumor. Only after assignment to one of these four categories can an
effective diagnostic strategy ensue. If the clinical and radiographic
information favors a diagnosis of malignant or aggressive benign bone
tumor, the clinician should refer the patient to an experienced orthopaedic
oncologist without performing additional diagnostic tests or a biopsy. If a
soft-tissue mass is five centimeters in diameter or larger on physical
examination, and especially if it is deep to the fascia, the patient should
also be referred to an orthopaedic oncologist, without additional
evaluation or biopsy, because of the relatively high probability that the
mass is malignant.